<tr>
    <td style='width:100px;height:30px;'>导出模版：</td>
     <td style='text-align:left;'>
     <select name='salesExportType' onchange="changeDownExport(this.value);">
     <option value='ar'>销售应收账单</option>
     <option value='normal'>销售实收账单</option>
     </select>
     </td>
</tr>
<script>
function changeDownExport(flag){
     if(flag == 'ar'){
          $('filename').set('value','销售应收账单导入');
     }
     if(flag == 'normal'){
          $('filename').set('value','销售实收账单导入');
     }
}
changeDownExport('ar');
</script>